Weft selecting, measuring and storing apparatus

ABSTRACT

In an apparatus for selectively feeding a weft yarn, one roller of a pair of continuously driven rollers has at least one peripheral groove with diverging sidewalls. The other roller has a similar peripheral groove, and the rollers engage to form a nip in which the grooves register to form an opening between the rollers. A thread guide is movably mounted for movement between a position in which it is in alignment with said opening, so as to maintain a weft yarn said opening, and a position in which it guides a yarn into driven engagement in the nip of the rollers at one side of said opening. Means are provided for selectively moving the thread guide between the two positions.

United States Patent [191 Vermeulen et al.

[ Dec. 16, 1975 WEFT SELECTING, MEASURING AND STORING APPARATUS [75] Inventors: Geert Jan Vermeulen; Adrianus Henricus Van Duynhoven, both of Deume, Netherlands [73] Assignee: Ruti-Te Strake B.V., Deurne, Netherlands [22] Filed: Oct. 10, 1974 [21] Appl. No.1 513,645

[30] Foreign Application Priority Data Oct. 11, 1973 Netherlands 7314025 [52] US. Cl 139/122 H; 66/132 R; 226/34; 226/181 [51] Int. Cl. D03D 47/36 [58] Field of Search 139/122 R, 122 H, 127 P; 226/178, 184, 34, 181-, 66/132 [56] References Cited UNITED STATES PATENTS 3,315,708 4/1967 Scheffel 139/122 Mizuno 139/127 Chattaway et al. 139/122 Primary Examinerl-lenry S. Jaudon Attorney, Agent, or FirmMarshall & Yeasting [5 7 ABSTRACT In an apparatus for selectively feeding a weft yarn, one roller of a pair of continuously driven rollers has at least one peripheral groove with diverging sidewalls. The other roller has asimilar peripheral groove, and the rollers engage to form a nip in which the grooves register to form an opening between the rollers. A thread guide is movably mounted for movement be- A tween a position in which it is in alignment with said opening, so as to maintain a weft yarn said opening, and a position in which it guides a yarn into driven engagement in the nip of the rollers at one side of said opening. Means are provided for selectively moving the thread guide between the two positions.

1 Claim, 5 Drawing Figures US. Patent Dec. 16,1975 Sheet 1 of2 3,926,224

US. Patent Dec. 16, 1975 Sheet 2 of2 3,926,224

WEFT SELECTING, MEASURING AND APPARATUS BACKGROUND OF INVENTION The invention relates to a weaving machine compris- STORING ing a plural weft conveyor, operated by a flowing fluid and adapted to weaving plural weft yarn colors, a yarn clamp being provided between the weft yarn supply of In this known machine the continuously rotating rollers associated with a predetermined weft yarn color are kept drivingly engaged mutually and with the weft yarn as long as the weaving with that color proceeds. The rollers of the roller pairs associated with the other colors of the weft yarn are kept out of engagement during this time interval mutually and with the weft yarn in that the rollers have been moved apart with respect to each other by a predetermined distance.

A disadvantage of this known construction is that with each color change relatively large roller masses are to be reciprocated, whereby the weft yarn tends to be damaged by impact between the engaging rollers.

SUMMARY OF THE INVENTION The invention aims at removing the restrictions of the known device, which are inherent in view of this disadvantage.

This aim is attained according to the invention in that the co-operating rollers for each weft yarn color are continuously peripherally engaged and co-operate with a changer element guiding the weft yarn, which element is controllable such that it keeps the weft yarn dependent on the color need in or out of engagement with the rollers.

Moving the weft yarn in and out of engagement with the rollers by means of the changer element is according to a further feature of the invention facilitated in that the engaging peripheral surfaces or surface zones are at least at one side flanked by peripheral surface portions extending from said peripheral surfaces or zones gradually away from each other. Said last-mentioned peripheral surface portions delimit as it were a receiving and guiding zone narrowing towards the adjacent engaging peripheral surfaces or surface zones, from which receiving zone the weft yarn may be led smoothly and positively towards the peripheral contact zones of both rollers and vice versa.

When weaving with two weft yarn colors a color may then be selectively brought in or out of engagement with the engaging roller surfaces simply from each of both of the ends of the roller pair.

When weaving with more than two weft yarn colors likewise a simple embodiment of the rollers may be realized, namely by dividing the co-operating peripheral surfaces of a single pair of rollers, in the axial direction, into a number of zones, wherein between every two adjacent peripheral surface zones a receiving and guiding space for at least one weft yarn is formed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a weaving machine comprising a yarn pulling device according to the invention, only those parts of the machine being shown which are directly related to the invention;

FIGS. 2 and 3 each show a schematic axial section through the pairof pulling rollers according to FIG. 1, in embodiments suitable for application in a weaving machine for weaving with two or more than two weft yarn colors respectively;

FIG. 4 is aschematic perspective view of the yarn preparation portion situated between the weft yarn supply and theinsert side of the weaving shed, when adapted for weaving with two weft yarn colors, and

FIG. 5 is a block diagram of the electric circuit insofar as it relates to the color changing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS reference number 1. From this packet the weft yarn 2 extends through a yarn brake 3, a pair of continuously driven and mutually peripherally engaging pulling rollers 4A, 48 a yarn buffering device 5 operated with blowing air and/or suction air, and a yarn clamp 6 towards the weft conveyor 7, e.g. constituted by an air operated blowing, nozzle. The rollers 4A, 4B are mounted in suitable bearings in the weaving machine, and are continuously driven in the operation of the weaving machine by any suitable driving mechanism. The weaving shed is schematically indicated by the line 8. Between theinsert side 9 of the weaving shed 8 and the weft conveyor 7 there. is provided a cutting device 11, while a suction nozzle 12 is situated at the opposite side 10 of the weavingshed, which is adapted for sucking in and after cutting by a second cutting device 13 sucking off the weft yarn ends projecting at that side. The blowing nozzle 7 produces at least during the weft inserting phase an air jet which tends to convey the weft yarn 2, extending through the nozzle, through the weaving shed 8. Conveying of said yarn only takes place, however, after the yarn clamp 6 at the beginning of the weft inserting phase has been opened. The rollers 4A, 4B in the meantime pull the yarn 2 continuously from the yarn packet. During the interval that no yarn conveyance by the yarn conveyor 7 takes place, the pulled yarn is stocked in the shape of a loop in the buffering device and kept ready for the next weft inserting phase. As so far. described the machine according to FIG. 1 is -of known construction. The novel feature is thatthe rollers 4A, 4B co-operate with a thread guide in the form of a changer element 14, provided with a guiding eye 14' for the weft yarn 2 and reciprocable in the direction of the arrow between operative and inoperative positions, in which it keeps the weft yarn in and out of engagement respectively with the co -operating peripheral surfaces of the rollers 4A, 4B.

In this manner therefore the yarn pulling operation may be interrupted, which is important in a plural color weaving process. When thereby, at the end of the weft stroke of a predetermined weft yarn color, transfer has to be made to a different weft yarn color, the changer element associated with the first-mentioned color is placed in its inoperative position-with respect to its pulling rollers, whereas the changer element associated with the new color in correspondence with the color p'r'ograrn is brought into its operative position with 3 respect to the co-operating rollers in order to place a weft yarn length of the new color in prepared position in its buffering device.

It will be clear that the yarn clamps provided between the weft conveyors and the buffering devices for the different colors have to be controlled correspondingly. The co-operation between the pulling rollers 4A, 4B and the associated changer elements is sufficiently reproduceable so that the length of the weft yarn ends projecting beyond the cloth may be restricted to an acceptable maximum. When bringing the changer element 14 from the inoperative into the operative position the weft yarn entering thereby between the cooperating peripheral surfaces of the rollers 4A, 4B is taken along immediately, that is practically slipfree, while on the other hand the yarn pull is interrupted, when the changer element is brought intothe inoperative position, at an accurately predeterminable point of time.

FIG. 2 shows that the co-operating peripheral surfaces of the rollers 4A, 4B engage each other along an axial width b and that said peripheral surface portions are flanked at both sides by peripheral surface portions 15 which gradually diverge away from the peripheral surfaces b. Said peripheral surface portions 15 delimit a wedge-shaped space into which the weft yarn is received when the changer element 14A or 14B enters its operative position and the yarn is positively guided towards the adjacent co-operating peripheral surfaces b of the rollers 4A, 4B. FIG. 2 shows likewise that the pair of rollers 4A, 4B may co-operate with two changer elements 14A and 14B, each positioned at an end of the roller pair, each of said elements being adapted to control the pulling of yarn of a predetermined color. The changer element 14A and 148 each consists of an arm which is pivoted to a fixed support and which terminates in a guiding eye 14A or 14 B. In order to move the guided weft yarn between its idle position and its driven position, the pivoted arms of the changer 14A and 14B are preferably controlled electrically, with the aid of solenoids 16A and 16B energized in accordance with the desired yarn pulling interval.

The embodiment according to FIG. 3 is destined for application to a machine which is adapted for weaving with four different weft yarn colors 2A-2D. Thefeto the rollers 4A, 4B co-operate with four axially spaced changer elements 14A-14D, the co-operating peripheral surfaces of the rollers 4A, 4B being divided 'axi-' ally, into four zones b.

The extreme left changer element 14A, as seen in FIG. 3, which guides the weft yarn 2A, co-operates with the rollers 4A, 4B in the same manner-as the left changer element 14A cooperates the rollers 4A, 4B in the embodiment according to FIG. 2.

Between every two adjacent peripheral surface zones b the peripheral surfaces of the rollers 4A, 4B are recessed such that a space 17 is provided, in which one of the three remaining weft yarn colors (2B, 2C, 2D) may be present without being taken along by the continuously rotating rollers, and from which the weft yarn may be brought between the adjacent pei'ipheral surface zones b by the associated changer element 14B,

or 14C, or 14D respectively, in the same manner as described with reference to FIG. 2.

In the embodiment shown in FIG. 4 by way of example, for weaving with two colors, the differently colored weft yarns 2A and 2B are pulled by a plural yarn pulling device 18 selectively from the stationary yarn packets 1A, 1B and supplied to a plural buffering device 19. The yarn pulling device 18 comprise's two continuously rotating and continuously peripherally engaging rollers which co-operate in a similar manner as described above with reference to the rollers4A, 4B, with a number of' changer elements 14A, 14B, corresponding to the number of colors to be woven.

The buffering device 19 comprises a buffering tube for each weft yarn color to be woven, in the case considered therefore two buffering tubes 5A and 5B. The yarn 2A or 2B, pulled by the yarn pulling device 18 from the yarn packet 1A or 1B, is supplied to the buffering tube 5A or 5B via a guide 20A or 20B and an injector 21A or 21B, preferably blowing continuously. Each of the buffering tubes 5A and 5B is a conventional buffering tube in which a loop of the weft yarn is maintained in extended condition by air flowing through the buffering tube away from the entrance of the tube. The weft yarn 2A or 2B leaving the buflering tube 5A or 5B,'is guided by a guide 22A or 22B towards the yarn clamp 6A or 6B, in order to be guided towards the weft blowing nozzle 7A or 7B.

From the foregoing description it will be understood that while a given yarn is being used to form the weft threads, the blowing nozzle 7A or 7B for that particular yarn is continuously supplied with flowing air and the rollers 4A and 4B are driven continuously so as to feed the weft yarn continuously at such a speed as to make available the necessary length of weft yarn for each weft insertion. Each weft insertion is then caused to take place, when the yarn 2A is in use, by opening the clamp 6A and then closing the clamp as soon as the weft has been inserted. While the weft yarn 2A is in use, the valve 23A is open and the clamp 3A also is open, while the valve 23B and the clamp 3B are closed and the yarn clamp 6B also remains closed. Each of these yarnclamps is a normally closed clamp which is provided with a solenoid as indicated in the drawings,

and which remains closed so long as the solenoid is not energized.

When the changer element 14B is in the operative position the weft yarn 2B is in operative engagement with the pulling rollers 4A, 4B and is continuously pulled from the packet 1B. The injector 21B operates in order to form the continuously supplied yarn 2B into a stocking loop in the buffering tube 5B,. the yarn clamp 6B being intermittently opened (during the weft inserting phase of the relative yarn) and closed (during the reed beating up phase) and the blowing nozzle 7B being supplied with air continuously, e.g. through the electromagnetically controlled valve 23B, in order to convey each time when the yarn clamp 6B is open a length corresponding to the weaving width, of the weft yarn 2B, through the weaving shed.

The pulling of the weft yarn of different color (in this case of the weft yarn 2A) has been stopped in that the changer element 14A is in its inoperative position with reference to the rollers 4A, 4B because the solenoid 16A which operates the changer element 14A is not energized. Therefore there is no supplying of weft yam to the buffering tube 5A. The stock of weft yarn present in the buffering tube 5A is zero since the pulling of the yarn 2A has been interrupted at the end of a period of weavingwith this weft yarn at a point of time namely at the end of a weft inserting phase in at which the previously prepared weft yarn length in the buffering tube 5A had just been used up.

This situation continues up till the moment that the color has to be changed. Thereto the changer elements 14A, 148, the yarn clamps 6A, 6B, the blowing nozzles 7A, 7B and any further elements, to be controlled dependent on the momentary color need, are connected, together with a color selection switch for each of the weft yarn colors 2A, 2B, in a control circuit (see FIG. 5). The color selection switches 24A, 24B are controlled by the color program, e.g. determined by a punched tape, magnetic tape, code disc or otherwise. At the moment of the color change, thus in the considered case at the end of the weft inserting phase of yarn 2B, the color selection switch 248 is opened and the color selection switch 24A is closed. As a consequence thereof the changer element 14B is brought into its inoperative position to which it returns whenever the solenoid 16B is deenergized so that the pulling of the yarn 2B is immediately interrupted. At the same time the changer element 14A is brought into its operative position by energization of the solenoid 16A, so that the pulling of the yarn 2A is started. The air supply of the blowing nozzle 7A is switched on by energizing of the solenoid valve 23A to open the valve whereas that of the blowing nozzle 7B is switched off. Further the yarn clamp 68 and yarn brake 3B are closed whereas the yarn clamp 6A and yarn brake 3A are opened. The stock of yarn present in the buffering tube 58 is zero at the moment. By closing the yarn clamp 6B the weft insertion of yarn 2A remains in abeyance, namely from the moment in which the last weft yarn 2B has been beaten up into the cloth. At that moment a switch 26 is closed, e. g. under the control of a cam 25 determining the starting point of time of the weft insertion whereby the energization circuit of the (electrical) yarn clamp 6A is closed, so that this clamp may open. The yarn clamp 6A then proceeds alternately opening and closing under control of the switch 26 until, according to the color program, a'next color change has to take place.

It will be clear that the above described principle is realisable for an arbitrary number of colors.

We claim:

1. In a weaving machine, apparatus for selectively feeding a weft yarn, comprising a pair of continuously driven rollers, one of which has at least one peripheral groove with diverging side walls, and the other of which has a similar peripheral groove, said rollers engaging to form a nip in which said grooves register to form an opening between the rollers, a thread guide which is movably mounted for movement between a position in 

1. In a weaving machine, apparatus for selectively feeding a weft yarn, comprising a pair of continuously driven rollers, one of which has at least one peripheral groove with diverging side walls, and the other of which has a similar peripheral groove, said rollers engaging to form a nip in which said grooves register to form an opening between the rollers, a thread guide which is movably mounted for movement between a position in which it is in alignment with said opening, so as to maintain a weft yarn in said opening, and a position in which it guides said weft yarn into driven engagement in the nip of the rollers at one side of said opening, and means for selectively moving said thread guide between said positions. 